Numerical Analysis of Nitrate in Groundwater Considering Topographical Characteristics and Climate Change

Changes in rainfall patterns due to climate change affect groundwater levels, which significantly influence the concentration and distribution of contaminants. This study used OpenGeoSys to compare and analyze the accumulation and dispersion of nitrate concentrations under different climate change scenarios, while reflecting the characteristics of mountainous and flat terrains. Groundwater recharge rates were calculated through the Water Table Fluctuation (WTF) method, using rainfall and groundwater level data. The simulation results linked to the SSP scenarios showed that, in mountainous areas, a rise in groundwater level (+2.1 m) led to the dispersion and dilution of nitrate, whereas in flat areas, low flow velocities resulted in nitrate accumulation. This study analyzed the impact of climate change-induced groundwater-level fluctuations on contaminant behavior and is expected to provide foundational data to develop strategies for groundwater management and pollution mitigation that are adaptive to climate change.